Efficient domestic hot water with air-source absorption heat pumps

Domestic hot water (DHW) is one of the largest energy loads in hotels, hospitals, care homes, sports facilities, apartment buildings and industry. In installations like these, where DHW demand is high and continuous all year, Robur GAHP A Plus air-source gas absorption heat pumps are a very high-efficiency solution that combines natural gas or LPG with renewable energy from the outdoor air.

Unlike a conventional boiler, an absorption heat pump does not generate all its thermal energy by burning gas. A significant part of the energy supplied comes free from the outdoor air through a water-ammonia absorption cycle, considerably reducing fuel consumption and CO₂ emissions.

Absorption technology applied to DHW production

Robur air-source absorption heat pumps use a water-ammonia thermodynamic cycle, in which the gas only supplies the energy needed to drive the absorption process, while the ambient heat in the outdoor air is used as renewable energy.

This technology produces hot water with a much higher efficiency than a traditional condensing boiler, and its performance remains stable even at very low outdoor temperatures. Thanks to the absorption cycle, the heating capacity is hardly affected by weather conditions.

Maximum efficiency all year round

The new-generation Robur GAHP A Plus reaches a gas utilisation efficiency (GUE) of up to 172 %, roughly equivalent to a COP of 4.3 according to the comparison criterion set by Robur. Even at outdoor temperatures of −7 ºC, it keeps an efficiency of close to 158 %, ensuring DHW production without auxiliary systems.

Benefits of the technology

• Energy efficiency of up to 172 % GUE.
• Hot water production up to 70 ºC, ideal for DHW.
• Savings of up to 40 % compared with high-efficiency condensing boilers.
• Very low electricity consumption, about a tenth of that of an equivalent electric heat pump.
• Natural refrigerant, exempt from the F-Gas regulation.
• Ready for gas blends with up to 20 % hydrogen (H₂ Ready).
• Standard and low-noise versions.

Recommended applications

Air-source absorption heat pumps are particularly suitable where there is a high annual demand for domestic hot water:

• Hotels and resorts.
• Hospitals and healthcare centres.
• Care homes.
• Sports facilities and swimming pools.
• Residential buildings with central DHW production.
• Industrial processes with continuous hot water consumption.

Its high flow temperature makes it easy to integrate into both new installations and energy refurbishment projects, reusing much of the existing hydraulic infrastructure.